Pinhole cameras are known. A pinhole camera typically includes a single small aperture (i.e., a pinhole) and does not include a lens. A pinhole camera typically collects light rays from a scene that pass through a common Center-of-Projection (CoP). A pinhole camera model describes the mathematical relationship between the coordinates of a three-dimensional (3D) point and its projection onto the image plane of an ideal pinhole camera. Pinhole camera models are commonly used as an imaging model for various computer vision tasks (e.g., object recognition, motion analysis, scene reconstruction, image restoration, etc.). The pinhole model is popular for at least two reasons. First, pinhole geometry is simple; it is uniquely defined by three parameters (the position of the CoP in three-dimensions) and its imaging process can be uniformly described by a conventional 3×4 pinhole camera matrix. Second, human eyes act as a virtual pinhole camera. For example, human eyes may observe lines as lines and parallel lines as converging at a vanishing point. Pinhole cameras, thus, are also commonly referred to as perspective cameras.
Multi-perspective cameras have also been used for computer vision. In general, a multi-perspective camera captures light rays originating from different points in space. Multi-perspective imaging models widely exist in nature. For example, a compound insect eye may include thousands of individual photoreceptor units pointing in slightly different directions. The collected rays by multi-perspective cameras generally do not pass through a common CoP and, thus, do not follow pinhole geometry. Multi-perspective imaging models may provide advantages for perceiving and/or interpreting scene geometry as compared with pinhole imaging models.
Crossed-slit cameras may be traced back to the crossed-slit anamorphoser, credited to Ducos du Hauron. The anamorphoser modifies a pinhole camera by replacing the pinhole with a pair of narrow, perpendicularly crossed slits, spaced apart along the camera axis. Image distortions appear anamorphic or anamorphotic and the degree of anamorphic compression closely matches the estimated distortion using the crossed-slit model. This brute-force implementation of crossed-slits suffers from low light efficiency and poor imaging quality.